Studies outlined are designed to determine the effects of diabetes mellitus on intestinal digestive-absorptive function and to elucidate the underlying mechanisms. Genetically diabetic animals are used to investigate the long-term effects of diabetes and to avoid the toxic effects of diabetogenic drugs. Studies on initial rates of transport of glucose analogs and representative amino acids revealed no significant changes in diabetic mice and hamsters. Studies on in vivo absorption will be done to correlate the results from in vitro studies. Changes in kinetic characteristics of uptake such as carrier affinity, maximal capacity, and permeability characteristics of brush border membrane vesicles will be evaluated. Studies on the digestive function of the intestine demonstrated significant increases in specific activities on hydrolases involved in the final stages of digestion of nutrients. The physiological role for the stimulation of enzyme activities in diabetes will be investigated. The relationship of spontaneous diabetes to glycolytic and gluconeogenic enzymes of the intestine will be determined. Diabetic mice exhibited elevated levels of serum and antral gastrin indicating gastrin's probable role in enhanced intestinal growth observed in diabetic mice. The role of hypergastrinemia and other factors such as hyperphagia in stimulation of intestinal growth will be evaluated.